Abstract: A bullet comprising a compacted mixture of copper powder comprising particles that are physically bonded to each other to form a cohesive and ductile microstructure is disclosed. Methods of making such a bullet through powdered metallurgy techniques, which provide sufficient properties to allow the bullet to be loaded into a cartridge and crimped without fracture are also disclosed. Such bullets have sufficient strength to maintain their integrity during firing but may fragment upon impact and can be formulated lead-free.

Abstract: A frangible metal article such as a bullet and a method for making it. The frangible metal article is formed from a mixture of metal particles and metal or metalloid binder material which is compacted into the desired shape, heated to a temperature above that needed to form at least one intermetallic compound but below the temperature of joining of the metal particles by sintering and below the temperature of formation of substantial amounts of a ductile alloy of the metal of the particles and the metal or metalloid binder material and then cooled. When such articles are formed into bullets they have sufficient strength to maintain their integrity during firing but disintegrate into powder on impact and can be formulated to be lead-free.

Abstract: A frangible metal bullet, a method for making it, and ammunition made therefrom. The frangible metal bullet is formed from a mixture of metal particles and metal or metalloid binder forming material which is compacted into the desired shape, heated to a temperature above that needed to form at least one intermetallic compound but below the temperature of joining of the metal particles by sintering and below the temperature of formation of substantial amounts of a ductile alloy of the metal of the particles and the metal or metalloid binder forming material and then cooled. Such bullets have sufficient strength to maintain their integrity during firing but disintegrate into powder on impact and can be formulated to be lead-free.